1. Field of the Invention
The present invention relates to an airview seaming technology, particularly to a method to automatically correct the airviews of the surroundings of a vehicle.
2. Description of the Related Art
Digital cameras are fast falling in price and have been widely used as auxiliary instruments of vehicles. As a driver is unlikely to watch several images simultaneously, some manufacturers have integrated several primitive images into a 2D surrounding airview, which is more suitable for human vision. The conventional technology uses three steps to achieve a panoramic airview, including distortion correction, view point conversion, and image seaming. However, the conventional technology needs human decisions and manual parameter setting in undertaking the three steps. Therefore, the conventional technology is inconvenient and time-consuming. Besides, the precision of the panoramic airview correction is likely to be degraded by errors of camera installation.
A Taiwan patent No. I320756 disclosed a technology, which uses a fisheye lens to capture surrounding images of a vehicle and uses distortion correction, view point conversion, and image seaming to obtain a single piece of airview, wherein a planar homography matrix is used to convert the view points. The prior art finds out identical features of the overlapped regions of the images captured by two different cameras for seaming the images. However, the present invention is characterized in using a blocking matching technology to automatically search for the feature points, whereby to realize the automation of airview correction. Further, the present invention can automatically compensate the installation errors of cameras.
A Taiwan patent No. 201103787 disclosed a technology, which uses a mapping table to correct image distortions, convert view points and seam images to obtain an airview. However, the prior art needs human decisions and manual parameter setting in image distortion correction, view point conversion and image seaming. Contrarily, the present invention provides an automatic corner point searching device and an automatic corner point matching device to replace human decision and manual parameter setting, whereby to achieve full automatic airview correction and higher-precision airviews.
Thus, the present invention proposes an automatic airview correction method to solve the abovementioned problems.